Overview

W32/HLLP.Philis.il is a file infecting virus. It searches for executable files on the infected machine to prepend its viral code. It is also responsible for dropping a dll file, which downloads password stealing trojans from various websites.

Minimum Engine

5600.1067

File Length

75691 Bytes

Description Added

2007-03-23

Description Modified

2007-03-23

Malware Proliferation

Characteristics

On execution, it copies itself in %WinDir%\Uninstall\ folder as rundl132.exe and adds a load registry entry to activate itself on reboot. It also creates the following registry entries:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\DownloadManager

HKEY_LOCAL_MACHINE\SOFTWARE\Soft\DownloadWWW\auto: "1"

It drops a file named RichDll.dll (detected as W32/HLLP.Philis.dll) in %WinDir%. It then injects this dll in processes Explorer.exe and IExplore.exe. This dll is responsible for opening a backdoor and also downloading other password stealing trojans such as PWS-Lineage from the following locations:

[REMOVED]43242.com

W32/HLLP.Philis.il searches for executable files and prepends its viral code to target files. It adds its 57KB code in front of the original file, so whenever that file is executed the virus is also executed.

The virus creates files with the name "_desktop.ini" in every folder that it visits while looking for executable files to infect. This is created as a hidden system file and contains the date on which virus was executed to visit the folder in which the file resides. The date is shown in yyyy/mm/dd format.

The virus tries to spread via existing network shares. It searches for all active machines within the subnet. When it finds an active machine it sends an ICMP ping request and waits for a response. After getting the ping response it tries to access the ADMIN$, IPC$ and any other shares that might exist on the machine. If the virus is able to access a shared resource, it first copies "_desktop.ini" to the root of the share to mark the share as visited and then infects executables present in the share. While infecting executables via a network share the virus does not limit itself to infecting specific file names as mentioned above. In the case of a shared printer, the viruses' infection routine effectively creates printer job to print the date as contained in "_desktop.ini" file that the virus tries to copy.

The virus terminates the following processes.

RavMon.exe

EGHOST.EXE

MAILMON.EXE

KAVPFW.EXE

IPARMOR.EXE

Ravmond.EXE

regsvc.exe

mcshield.exe

Symptoms

Presence of %WinDir%\RichDll.dll

Presence of registry entries as described

Presence of hidden system files named _desktop.ini in many folders.

Increase in size of EXE files

Method of Infection

W32/HLLP.Philis.il is a file infecting virus. Infection starts with manual execution of the binary. For spreading, the virus also relies on improperly configured/protected (open) shared drives.